II. Anatomy: Superior (Rostral) Midbrain Components
- Superior colliculus
- Superior (rostral) bump on each side of the upper Midbrain
- Visual reflex center (visual function, orientation of head and eyes)
- Aqueduct
- Single small midline CSF conduit
-
CN 3 nucleus (Oculomotor Nerve)
- Medial, immediately anterior to aqueduct
- Cranial Nerves course anteriorly, and exit in the superior Midbrain at the midline
- Medial Geniculate Body
- Communication relay between the inferior colliculus and the auditory cortex
-
Spinothalamic Tract
- Continued pain and TemperatureSensation tracts from the spinal cord
-
Medial Lemniscus
- Proprioception Sensation from Posterior Columns (via Internal Arcuate Tract)
- Within the tract, head is represented anteriorly and legs posteriorly (as if standing on head)
- Red Nucleus
- Reflexive movement (e.g. crawling)
-
Substantia Nigra
- Substantia Nigra's pars compacta produces Dopamine which is transmitted to the Dorsal Striatum
- Parkinsonism may result if deficient Dopamine production
-
Corticospinal tract
- Continued motor tracts to the spinal cord
- Head is represented anteromedially and legs posterolaterally
III. Anatomy: Inferior (Caudal) Midbrain Components
- Inferior colliculus
- Inferior (caudal) bump on each side of the lower Midbrain
- Aqueduct
- Single small midline CSF conduit
-
CN 4 nucleus (Trochlear Nerve)
- Medial, immediately anterior to aqueduct
- Cranial Nerves exit posteriorly and immediately cross the midline (unique to CN 4)
-
Spinothalamic Tract
- Continued pain and TemperatureSensation tracts from the spinal cord
-
Medial Lemniscus
- Proprioception Sensation from Posterior Columns (via Internal Arcuate Tract)
- Crossings (Decussation)
- Superior Cerebellar Peduncles Decussation
-
Substantia Nigra
- Substantia Nigra's pars compacta produces Dopamine which is transmitted to the Dorsal Striatum
- Parkinsonism may result if deficient Dopamine production
-
Corticospinal tract
- Continued motor tracts to the spinal cord
IV. Anatomy: Images
- Rostral (superior cross-section)
- Caudal (inferior cross-section)
- Other cross sections
Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
V. References
- Gilman (1989) Manter and Gatz Essentials of Neuroanatomy and Neurophysiology, Davis, p. 81-96
- Goldberg (2014) Clinical Neuroanatomy, Medmaster, p. 24-39
- Netter (1997) Atlas Human Anatomy, ICON Learning, p. 108-12
Calculation (FPnotebook.com: DrBits) Open in New Window
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Related Studies
| Definition (FMA) | Organ component of neuraxis that has as its parts the tectum, cerebral peduncle, midbrain tegmentum and cerebral aqueduct. Examples: There is only one midbrain. |
| Definition (NCI_CDISC) | The uppermost portion of the brainstem located between the pons and the diencephalon. The midbrain contains the cerebral peduncles, oculomotor, trochlear and red nuclei, substantia nigra and various other nuclei and tracts. (NCI) |
| Definition (NCI) | The uppermost portion of the brainstem located between the pons and the diencephalon. The midbrain contains the cerebral peduncles, oculomotor, trochlear and red nuclei, substantia nigra and various other nuclei and tracts. |
| Definition (CSP) | develops from the middle of the 3 primary vesicles of the embryonic neural tube, between the prosencephalon and rhombencephalon, later forming the tectum and cerebral peduncles. |
| Definition (MSH) | The middle of the three primitive cerebral vesicles of the embryonic brain. Without further subdivision, midbrain develops into a short, constricted portion connecting the PONS and the DIENCEPHALON. Midbrain contains two major parts, the dorsal TECTUM MESENCEPHALI and the ventral TEGMENTUM MESENCEPHALI, housing components of auditory, visual, and other sensorimoter systems. |
| Concepts | Body Part, Organ, or Organ Component (T023) |
| MSH | D008636 |
| SnomedCT | 61962009 |
| English | Mesencephalon, Mesencephalons, Midbrain, Midbrains, mesencephalon, Structure of midbrain, mesencephalic, midbrain, MBr, BRAIN, MIDBRAIN, MIDBRAIN, Midbrain structure (body structure), Midbrain structure, Mesencephalon, NOS, Midbrain, NOS, Mid-brain |
| French | Isthme du cerveau, Mésencéphale, Cerveau moyen, Isthme de l'encéphale |
| Swedish | Mitthjärna |
| Czech | mezencefalon, střední mozek |
| Finnish | Keskiaivot |
| Russian | MOZG SREDNII, МОЗГ СРЕДНИЙ |
| Japanese | 脳脚, 中脳 |
| Portuguese | Cérebro Médio, Mesencéfalo |
| Italian | Cervello di mezzo, Cervello medio, Mesoencefalo, Mesencefalo |
| Croatian | MEZENCEFALON |
| Latvian | Vidussmadzenes |
| Polish | Śródmózgowie |
| Norwegian | Midthjerne, Mesencephalon |
| Spanish | cerebro medio, estructura del mesencéfalo (estructura corporal), estructura del mesencéfalo, mesencéfalo, Cerebro Medio, Mesencéfalo |
| German | Mesenzephalon, Mittelhirn |
| Dutch | Mesencephalon, Middenhersenen |
